New scientist 8 october 2016 English magazine

In this section @ The limits of human lifespan, page 10 @ Is it time to worry about North Korea's nuclear plans?, page 18 @ Artificial intelligence gets common sense, page 22 FIELD N

'WORRYING TIMES

The truth about the anxiety epidemic

LOST WORDS The birth and death of

130 NOT OUT What's the upper limit of longevity?

THE REACTION THAT WILL

CHANGE THE WORLD

Crack it and we can burn fossil fuels forever

WORLD

CHANGERS |

ta»

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Antarctica has been inspiring explorers and ` sie)

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CROSS THE ANTARCTIC CIRCLE

Visit the Falkland Islands with their

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Crack itand we can burn

fossil fuels forever

36 Lostwords

Language birth and death

18 Nuclear power play

Time to get serious about

North Korea's bomb

10 130notout

The limits of longevity

9 Delightofthe bumblebee Insects get emotional

te eh Rea!

Bie ee sees

ad eh tere ees ts!

Crt @ and we Cn bara torel bards forever

eS ee) ee) 2 a3.) SS sx~«

Coming next week

The loss of a language is not always a

disaster Ahard line on crime can backfire

News

UPFRONT

Key species score a conservation victory

Rosetta’s final act Nobel prize round-up

THIS WEEK Hidden ice found inside Hawaiian volcano Bees can be optimistic and happy The limits

of human lifespan China wants a space plane for tourists Men get violent if outnumbered by women Artificial killer

cells mimic simple ecosystem

IN BRIEF Budgies always swerve right Cannibal

galaxy Bendy, bouncy 3D-printed bones

Analysis

North Korea's nukes Is it time to start worrying about Kim Jong-un's nuclear plans? COMMENT

For an optimum Brexit deal, take your time

What should we do if insects have feelings? INSIGHT

Elon Musk‘s vision alone won't get us to Mars

Technology

Artificial intelligence gets common sense 3D printing on the move Material morphs to its own molecular clock

Worrying times (see left)

Lost words The birth and death of a unique language

editing without calling for tough regulations

Furry friends, not What cats are really like

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The loss of a language Is not always an unmitigated disaster

DOES it matter if a language dies out? The orthodox answer is that

it does, because every language is

a repository of ideas and culture

and embodies a unique way of looking at the world The planet

only has about 7000 languages;

the extinction of even one diminishes the sum total of

human knowledge

But in some cases, extinction

can be seen ina more positive

light Take Al-Sayyid Bedouin

Sign Language (ABSL), restricted

to about 1000 users in a small

Israeli village with a high level of congenital deafness The language seems doomed by the spread of

Israeli sign language (see page 36)

The instinctive reaction is regret, and from a linguistic

perspective the loss of ABSLisa genuine shame It is a fascinating

language that has kept linguists

busy since it came to their attention around 15 years ago

But for the deaf villagers, Israeli

sign language is an upgrade: it allows them to speak to tens of thousands of people rather than

a few hundred, and enables them

to work and marry outside the village It is hard to see that as anything other than progress

The same is sometimes true for other endangered languages: they die out because people abandon them in favour of ones that serve

their needs better

Technology also softens the

blow, as endangered languages

can now be captured in detail —

which also means they could eventually be brought back from the dead, much as the language

of the Israelites was in the 19th

century Hebrew is now the first language of 9 million people

Linguists instinctively decry

the loss of language muchas

conservationist biologists once mourned the loss of every single

species But conservation is in

the midst of a paradigm shift,

moving towards acceptance that not all species can be saved, that invasive species are not always

bad and that human-engineered

ecosystems are not necessarily

inferior to natural ones Perhaps our attitudes to language

extinction are due fora similar

heretical change @

Tough on the causes

ONE of the worst spectacles of the

US presidential election has been

the resurgence of racially charged

politics Donald Trump is stoking fears of an explosion of violent crime in inner cities —a tactic widely seen as a racist dog whistle

Unlike lots of Trump's “facts”,

there is a grain of truth in this one

There has been a recent rise in violent crime in some major cities Solving this, and dispelling

racial tensions, should be high on

the political agenda

Conservatives and liberals will

disagree on the causes, but now

researchers have uncovered a

counter-intuitive factor: areas

with more women than men have

higher levels of violent and sexual crime (see page 12)

In the US, skewed sex ratios are

common in African-American

communities, where high levels of

male mortality and incarceration

mean there are nine or fewer adult

males for every 10 women

Census data reveals the depth

of the problem The vast majority

of white and Hispanic people live

in communities with roughly equal sex ratios More than 90 per

cent of black people do not

Sex ratios are clearly not the only factor in play But those who advocate tough-on-crime policies

with high levels of incarceration may be unwittingly fuelling the

fire they are trying to put out

PRETZELS and recycling featured

in this year’s Nobels as New

Scientist went to press

The physics prize went to three

British scientists, David Thouless

at the University of Washington,

“Topology helped to show

Duncan Haldane at Princeton

University and Michael Kosterlitz

at Brown University They looked

at superconductors and other

unusual states of matter using

topology, the mathematical

description of shapes

Topologically, a bagel is different

froma pretzel because one has

one hole while the other has two

Thouless and Kosterlitz used

topology to show how

superconductivity can appear in

extremely thin materials

Haldane used the same ideas to

explain the magnetic properties

Haldane said he “was very

surprised and very gratified” to

receive the award

Many had expected the discovery of gravitational waves

to win, but the LIGO team’s announcement just missed the

Nobel cut-off date of 31 January

The prize in physiology or

medicine went to Yoshinori

Ohsumiat the Tokyo Institute

of Technology for his work on autophagy, the process by which cells recycle and repair

themselves His discoveries are

vital for understanding how cells respond to stress and infection

Rosetta’s final bow

GOODBYE, Rosetta On 30 September,

the European Space Agency probe

landed on comet 67P/Churyumov-

Gerasimenko, in a spectacular finish

toits two years spentin orbit around

the space rock

Rosetta, never designed to land,

was probably badly damaged on

impact, despite comingin ata speed

of just 1 metre per second Its last

signal, transmitted at the moment of

landing, reached Earth at 12:19 BST

We will never hear from it again

The mission team hugged, clapped

and cried as Rosetta’s final moments were confirmed “I can announce full

towards 67P,” said Rosetta mission

manager Patrick Martin “Farewell

Rosetta, you've done the job That

was space science atits best.”

Wildlife wins

ITHAS been a red-letter week for

many of the world’s most iconic and threatened species The only

tinge of disappointment was a

failure to win complete protection for elephants and lions

Overall, the meeting of the Convention on International Trade in Endangered Species of

Wild Fauna and Flora, in

Johannesburg, South Africa, voted

en masse to back outright bans on

the wildlife trade These cover the

parts and tissues of a whole host

of threatened species, including

Pretty in pink

Rosetta launched in 2004 and

spent 10 years catching up with 67P

Itreached the cometin August 2014

and beamed back images of analien

landscape waiting to be explored

In November that year, Rosetta’s

companion lander, Philae, made a

bumpy touchdown and survived fora

few days on the comet before being

lost - though Rosetta did eventually

find itagain

‘As comet 67P moved away from

the sun, Rosetta’s solar panels delivered less and less power, meaning the mission would always

have to end now,

“Everybody is very sad On the

other hand, the mission end had to

come, and this is a spectacular way

‘to doit,” said Paolo Ferri, head of

ESA mission operations

African grey parrots, all species of pangolins, and Barbary macaques

“Most of the decisions favour

protection of animals for the

long term, so overall it’s beena

very strong pro-conservation

agenda,” says Kelvin Alie from the

International Fund for Animal

Welfare

Several species of sharks and rays were also newly listed under

the convention, and countries

voted to defeat a controversial proposal by Swaziland to permit

sales of white rhino horn But a

motion to expand protection to all African elephants failed

Baby dragons

IT WAS touch and go fora while But the elusive pink aquatic

salamanders that hatched inside

Slovenia's Postojna Cave about four months ago have survived

the most difficult stage of their

lives, reaching adolescence

“These are the only baby

dragons in the world known

to humanity,” says SaSo Weldt, amember of the conservation team taking care of the creatures, called olms

For new stories every day,

They were once only known

from specimens washed out of

caves by flooding and legend had

it they were baby dragons—a

nickname that stuck They can live

to be 100 years old and only lay

eggs once or twice a decade

So it was remarkable to see

64 eggs laid by a single individual

earlier this year They were placed

inan aquarium within the cave In

total, 22 eggs hatched, and all are

still alive and developing better

than expected, says Weldt Small

populations and water pollution

in its habitat in the Dinaric Alps

in the Western Balkans means the

species is classed as vulnerable

Rocket escape d

SPACE flight firm Blue Origin

‘was preparing for its most

dramatic trial yet as New Scientist

went to press: a test of an in-flight

escape system, designed to carry

future space tourists to safety in

an emergency

The company has already

flown its reusable New Shepard

rocket four times, launching

its uncrewed capsule into space

and then returning the rocket

safely to the West Texas desert

The escape system is designed

to separate the capsule from

the rocket For the test flight,

it will jettison the capsule 45

seconds after launch, when

the rocket has climbed nearly

5000 metres

The capsule, with room for six,

will blast its motor for less than

2seconds, enough to carry it away

to safety But in doing so, the

motor will knock the rocket back

with a force of more than

300,000 newtons, likely inflicting

severe damage on it

As the capsule parachutes

back to Earth, the rocket will most

probably plummet to the ground

Still filled with unused fuel, its

landing will be decidedly

explosive rather than soft

If New Shepard somehow

manages to survive, the company

says it will put it ina museum

it newscientist.com/news

Frog beats fungus

FOR decades a deadly fungus has been killing amphibians around the world, driving many to the brink of extinction, or worse

But now one frog’s recovery

shows that, with a little luck and

habitat preservation, some may evolve resistance after all

The Sierra Nevada yellow-

legged frog from the mountains

of California has been declining

for more than 100 years, due to

non-native predatory trout and the deadly chytrid fungus

“By the early 2000s, it had

disappeared from 93 per cent of

60 SECONDS

its historical localities,” says

Roland Knapp at the University of California’s Sierra Nevada Aquatic Research Laboratory

But its numbers are recovering

by an average of 11 percent per year, according to Knapp’s team, who analysed 7000 population surveys from the past 20 years in Yosemite National Park (PNAS, doi

org/brch)

There are fewer non-native fish

And, the frogs have developed some resistance to the fungus

“This shows there is hope that at

least some species can recover,

given the time and the habitat in

which to doit,” Knapp says

Hurricane Matthew batters Haiti

HAITI has been pummelled by

hurricane Matthew, which brought flooding and violent winds when it

hit on Tuesday One person had been

killed as New Scientist went to press

One of the strongest Atlantic

storms for nearly a decade, the

hurricane could dump up to a metre

of rain and generate winds of 230

kilometres an hour, raising fears

about flash floods and mudslides in

the western hemisphere's poorest

country

Thousands have been evacuated

from parts of neighbouring

Dominican Republic, and heavy

rain and wind has hit Jamaica,

with flooding blocking roads in the

capital, Kingston

Rural areas in south-west Haiti are

Notjust another storm

forecast to see the heaviest rain and

most punishing winds

“Wherever that centre passes

close to would see the worst winds

and that’s what's projected to happen for the western tip of Haiti," says John

Cangialosi at NOAA'S National

Hurricane Center in Miami, Florida

Rain is also a major concern, he adds

The Category 4 hurricaneis

forecast to move north over eastern Cuba and then the Bahamas, before

striking the US east coast later this

week Florida and parts of North

Carolina have already declared states

of emergency

Matthew briefly reached the top

classification, Category 5, becoming

the strongest hurricane in the region

since Felix in 2007

SpaceX investigation

SpaceX has launched aninquiry

into howits Falcon 9 rocket blew up

during aroutine testa month ago According to the Washington Post,

this means SpaceX has not ruled out

the possibility of sabotage, although

thatremains unlikely Congressman

Mike Coffman has urged government

agencies to take over the case, to protect future NASA crewsslated to fly with SpaceX to the ISS

The ugly truth

Unattractive friends may make you

look more fanciable, tests with

volunteers suggest They had to rate pictures of different faces for

attractiveness, viewing them singly

at first, then again with images of

less attractive people alongside The

original faces scored more highly the

second time around (Psychological

Science, doi.org/brbn)

Bees on their knees

Bees have appeared onthe US

endangered-species list for the first

time All native to Hawaii, the seven

species of yellow-faced bees are

threatened by non-native animals

and by development The bees

pollinate some of Hawaii's

indigenous plant species, many of

whichare themselves threatened

Poles’ pro-choice strike

Thousands of women in Poland went

onstrike on Monday to protesta

planto ban abortions The proposal, fromananti-abortion grassroots

campaign, is being examined by

aparliamentary commission and

would make all abortions illegal,

even incases of rape or when the

woman'slifeis at risk

Atitan’s footprints

One of the largest ever dinosaur

footprints has been unearthed in

the Gobi desert The well-preserved

fossilis 106 centimetres long and

77 centimetres wide, and is thought

to have been made by atitanosaur -

along-necked herbivore that may

have been 20 metres tall

8 October 2016 | NewScientist | 7

“TO SEE children who would have

been dead sitting and standing

is something I never thought I

would see.”

Francesco Muntoni, at

University College London, is

talking about videos of children

given an experimental drug for

treating spinal muscular atrophy

This genetic disorder involves

the deterioration of nerves

connecting the brain and spinal

cord to the body’s muscles

Children with the severest form

can’t sit upright and seldom

survive past the age of 2 Yet a few

parents have posted videos online

showing children given the drug,

called nusinersen, who appear to

be sitting and even walking with

assistance

The trial of nusinersen was

stopped in August when it

became clear it was effective,

making it unethical not to give the

real drug to those on the placebo

The full results haven't yet been

published, but what has been

revealed so far of this “antisense”

therapy suggests we have

overcome the biggest obstacle -

how to deliver such therapies — at

least in disorders that affect the

nervous system The breakthrough

could open the floodgates for

similar treatments for neurological

conditions such as Huntington’s,

motor neurone disease and

possibly even Alzheimer’s

Antisense drugs are essentially

pieces of DNA that bind to specific

RNAs - the recipe that cells use

to make proteins By binding

to RNAs, they can block the

production of proteins, or

alter their form

These drugs have the potential

to prevent or cure many diseases

But there’s been a huge snag: if

naked DNA is injected into people, ZEPHYR/SPL

8 | NewScientist | 8 October 2016

it doesn’t last long, let alone get

into cells So biologists have spent decades trying to create synthetic

forms that can survive in the

body They have strengthened the

DNA backbone, for example, to

help it bind more strongly to RNA

They have also made tweaks that help it enter nerve cells

Nusinersen is one such modified antisense drug Reports

of its success have created great

excitement among parents of

children with spinal muscular

atrophy, but we need to be

cautious about individual reports, says neuroscientist James Sleigh

at the University of Oxford

Even if the final results show

nusinersen doesn’t work as well

as hoped, there is still cause

for optimism Animal studies,

and postmortems of children

who died despite being given

nusinersen, show widespread

distribution of the antisense

molecule in the brain and spinal

cord, says Muntoni, who has

helped develop and test therapies

suchas nusinersen

These findings, and others,

show it is possible to get antisense

molecules into nerve cells,

meaning improved versions

should soon become available

“Tthink it will happen surprisingly quickly,” says Edward

Wild at the National Hospital for Neurology and Neurosurgery in

“It became clear that the drug was effective, meaning it was unethical tokeepg

London, who is part of a team

testing an antisense drug for

Huntington’s disease

This inherited condition remains untreatable despite decades of attempts to develop

therapies With the delivery

problem seemingly cracked, Wild thinks that will soon change The Huntington’s antisense drug that

ing the placebo”

Next on thelist: Huntington's

Wild’s team is trialling has passed initial safety tests with flying

colours

Such therapies could be used to

treat a range of disorders, possibly including Alzheimer’s There is

no single mutation that causes Alzheimer’s, says Wild, but we know of several gene variations

that increase the risk of the

disease In theory, blocking the production of proteins encoded

by these genes could delay or

prevent people becoming ill

The downside of antisense treatments is that repeat doses are required at least every few

months, and often for life The

drugs have to be injected directly

into the cerebrospinal fluid,

which flows around the brain and spine This procedure, calleda

lumbar puncture, can cause side

effects including headaches and back pain

But Muntoni and colleagues may have found a way to modify the antisense molecules so they

can cross the blood-brain barrier,

meaning they can be injected into

the bloodstream Animal studies

published last month suggest this approach works well, Sleigh says, but it has not yet been tested in people

The advent of therapies for

genetic conditions considered untreatable could change the way

we approach them If treatments

become available for childhood disorders such as spinal muscular atrophy, it will mean children

should be tested for the condition

at birth so they can begin therapy

as soon as possible

It could also change the way adults approach genetic sequencing of their own genes

At present, most people who have their genome sequenced opt not

to find out if they have inherited

diseases such as Huntington’s,

preferring not to know their fate But if it becomes treatable and

perhaps even preventable, they may wish to start therapies early

“As soon as we have something that works, people will want to get

tested,” says Wild m

In this section

@ The limits of human lifespan, page 10

@ Is it time to worry about North Korea's nuclear plans?, page 18

@ Artificial intelligence gets common sense, page 22

FIELD NOTES Mauna kea, Hawai

The volcano that

hides ice like Mars

Alice Klein

THEY are both breathtaking,

in quite different ways: the

thin air 4200 metres up, and

the majestically rugged, alien

landscape at my feet

Tam onthe summit of Mauna

Kea, the highest point in Hawaii

The red-brown basalt and barren

surface of the dormant volcano

conjure up images of Mars

It was in the Pu’u Wekiu crater,

in 1969, that the geophysicist

Alfred Woodcock dug beneath the

rocky exterior and discovered

a hidden ice world But when

Norbert Schorghofer, an

astronomer at the University of

Hawaii at Manoa, stumbled across

Woodcock’s papers decades later,

he was baffled How could ice

persist in an area where the

average temperature is 4°C?

To try to solve this puzzle,

Schorghofer has enlisted the help

of geophysicist and permafrost

expert Matthias Leopold at the

University of Western Australia in

Perth The goal of the expedition

Ihave come on is to find out

whether the subterranean

ice patch still exists

Schorghofer buried some

temperature sensors here in 2013,

and when we get to the third of these, a metre deep in the centre

of Woodcock’s old surveying area,

he lets out a whoop of excitement

The temperature here is freezing

To investigate further, Leopold spaces out 20 steel electrodes, each the size of a tent peg, across the survey area These generate an

electric field that can find frozen

ground up to 50 metres deep by measuring resistivity Unlike drilling, it preserves the landscape that local people hold sacred

The readings show that the ice

is still there, but its horizontal

“Sadly, time is running out for a precious window on how and why buried ice forms on the Red Planet”

extent has shrunk from 600 to

200 square metres, andits depth

halved to just 5 metres Global warming may have played a part

in this, but it’s hard to tell without

DON'T worry, bee happy Bumblebees

may experience something like

happiness after getting a treat,

making them take a more positive

view of things

Clint Perry at Queen Mary

University of London and his team

trained 24 bumblebees to associate

two locations in the lab, each of a

particular colour, with sugar water or

plain water They then measured the

time it took them to explore a new site

located midway between the two, and with an intermediate colour chosen

to make the bees unsure whether it contained a sweet reward or not

Half of the bumblebees received a sugar treat before the test, and these entered the ambiquous middle station more quickly than those that didn't It wasn't simply that these were more active because of the energy boost:

the effects seem to be down to the neurochemical dopamine, which plays

a role in the reward system in humans

geological and meteorological data tocome up with atheory of

why the buried ice persists The

most plausible explanation is

that it forms at night, when

temperatures drop below zero and icy air can swirl down the

steep crater and seep into the

porous, rocky ground Any ice formed would normally melt in

the daytime heat, but this patch sits in a dark crater

Mauna Kea is one of the best

models on Earth for studying ice within the tropics of Mars, says Schorghofer Most of the Red

Planet's ice is at the poles, but photos have identified signs of

Alien terrain, but not off-world

buried ice towards the equator

Just like with Pu’u Wekiu, these

spots lie in shadow inside the steep craters that punctuate the

planet’s surface

Not much is known about ice

away from Mars’s poles, so Mauna

Kea’s ice is a precious window on how and why it forms But sadly,

its time is running out With

climate change, Schorghofer believes the Mauna Kea ice will disappear over the next 50 years

As we drive back down, the only visible hint of where we have been

is the volcanic ash on our faces

But hopefully, this won't be my

last trip to Mars &

were blocked, the effect was gone

The treat also helped bees return to feeding more quickly after a simulated

predator attack (Science, doi.org/

brbc) This suggests that bumblebees carry out behaviours that go along with feelings, says Perry

It’s exciting to see a clear demonstration of something like emotions in bumblebees, says Eirik Sevik at Volda University College in Norway - although he isn’t surprised

“They have brains that function in pretty much the same ways as ours,” he says “The hard partis demonstrating it.” Emily Benson @

8 October 2016 | NewScientist | 9

THIS WEEK

Is our maximum

lifespan 115?

Clare Wilson

OUR life expectancy has been

climbing for decades — but how

much further can we push it?

The maximum lifespan for

most people may be around 115,

because of the innate limits of the

human body, according to new

research The few who have gone

beyond this age are rare outliers,

says Jan Vijg of the Albert Einstein

College of Medicine in New York

By analysing demographic

records, Vijg’s team has found

that maximum lifespan has not been rising in step with the average lifespan The record for the oldest living person climbed

to around 115 in the 1990s, after

which it has broadly plateaued

Although Jeanne Calment,

a French supercentenarian who has the longest confirmed human

lifespan on record, reached 122 before she died in 1997, her record

has gone unbroken for nearly two decades It shows we are

not seeing increasing numbers

breaking the 115 barrier, says Vijg

The team analysed more than

acentury’s worth of records from the four countries with the largest

documented number of people

aged 110 or over—the UK, US, France and Japan

They found that the rise in average lifespan is mostly caused

by people dying later at ages below about 110 For people older

than that, improvements in

survival fall off sharply (Nature,

DOI: 10.1038/nature19793)

But James Vaupel of the Max

Planck Institute for Demographic Research in Rostock, Germany, says many predictions about

limits to lifespan have been

proven wrong, as records have

been repeatedly broken “It is

disheartening how many times

the same mistake can be made,”

he says

At the start of the 20th century, average lifespan in the West was

inthe mid-4os, and has risen

to about 80 today Much of the initial rise came from fewer

child deaths Around the 1970s

onward, further increases in life

expectancy have been driven

by older people dying later

This is mainly thanks to better healthcare, such as widespread

use of medicines to lower blood pressure and cholesterol levels Tom Kirkwood of Newcastle

University, UK, disagrees with the

idea of alimit to human lifespan:

“The idea does not really fit what

we already know about the

biology of the ageing process

There is no set programme for ageing —the process is driven by the build-up of faults and damage

in the cells and organs of the body,

which is malleable.”

Richard Faragher of the

University of Brighton, UK, thinks

innate limits on lifespan are

“plausible” - yet the findings don’t necessarily mean we can’t extend

our lifespan further in future

“Jam positive that the human

maximum lifespan could be raised beyond 122 using technologies

that exist now,” he says

China's giant

spaceplane fits

in 20 tourists

EVEN China can't resist the lure of

‘space tourism A state-backed firm is

developing a gigantic craft that may

one day fly 20 passengers to the edge

of space

The China Academy of Launch

Vehicle Technology in Beijing has

designed a spaceplane that can be

scaled up to carry a large number

of people, academy rocket scientist

Lui Haiquang told the International

Astronautical Congress in Guadalajara,

Mexico, last week

10 | NewScientist | 8 October 2016

There is stiff competition Big

names include Virgin Galactic, whose

SpaceShipTwo spaceplane will offer

six passengers trips to near-space, and XCOR, whose proposed Lynx

vehicle will fly a single passenger next

toa pilot But academy team leader

Han Pengxin and his colleagues

believe there will be enough

consumer demand to builda

higher capacity spacecraft

Han team has designed two

versions of a spaceplane that takes off

vertically under its own rocket power

The first has a mass of 10 tonnes and

a wingspan of 6 metres This one, he says, should be able to fly five people

to an altitude of 100 kilometres -

where space officially begins - at

speeds up to Mach 6, giving 2 minutes

of weightlessness

Buta scaled-up, 100-tonne version,

with a 12-metre wingspan, could fly

20 people to 130 kilometres at Mach

8, with 4 minutes of weightlessness

The larger spacecraft is fast enough to

help deliver small satellites into orbit,

with the help of a small rocket stage

add-on that would sit on top of the

vehicle They also intend to make it

reusable, so each plane should be

good for upto 50 flights

He imagines flights will take off

will carry people when itis considered

safe enough Han predicts that a ride

will cost between $200,000 and

$250,000

Some remain sceptical, however

“The fact that they think they can test

fly in the next2 years is remarkable,”

says Roger Launius at the Smithsonian

Institution’s National Air and Space

Museum in Washington DC, who was

concerned by the lack of technical

details So the onus is on the academy

to prove this is more than a paper

spaceplane, he says “Itis always

easier to draw illustrations and talk

Possibilities than to build and fly

spacecraft.” Paul Marks ll

Six leading cosmologists, one amazing day of discovery Hear how

Einstein's relativity continues to revolutionise our view of the cosmos and

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By the end of the day, you'll feel like an expert too

THE BIG THEMES:

Get to grips with gravitational waves, the big bang, dark matter and

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Tasneem Zehra Husain, David Kaiser and Priya Natarajan

THIS WEEK

Men get violent if

women are aplenty

MORE meninevitably means

more testosterone-fuelled

violence, right? Wrong, according

toan analysis exploring how

ratios of men to women affect

crime rates across the US

Inareas where men outnumber

women, there were lower rates

of murders and assaults as well

as fewer sex-related crimes,

including rapes, sex offences

and prostitution Conversely,

higher rates of these crimes

occurred in areas where there

were more women than men

Ryan Schacht at the University

of Utah in Salt Lake City and his

colleagues analysed sex-ratio data

from 3082 US counties, provided

by the US Census Bureau in 2010

They compared this with crime

data for the same year, issued

by the US Federal Bureau of

Investigation They only included

information about women and

men of reproductive age

For all five types of offence

analysed, rising proportions of ANDREW

Artificial cells

mimic life and

obliterate prey

CELL-LIKE structures have been

designed to kill another population

of artificial protocells, mimicking a

crucial step in the evolution of life:

creatures eating one another

The hope is that they could one day

be custom made to deliver drugs And

they might just help us understand

how complex cellular communities

first evolved

We think protocells were the

microscopic precursors to living cells

Building artificial protocells from

substances such as fatty acids and

proteins allows us to study how life

might have originated Stephen Mann

12 | NewScientist | 8 October 2016

men ina county correlated

with fewer crimes -—even when

accounting for other potential contributing factors such as poverty The results suggest that current policies aimed at defusing

at the University of Bristol, UK, and his team made a community of these cells

to find out if they would display the

classic ecological setup of predatory

behaviour

They designed a death match

between two protocell populations

The predator cells were positively

charged droplets containing a

protein-degrading enzyme Their prey

were negatively charged capsules of

protein encircling a bit of DNA

The cells were attracted by their

opposing charges, and the enzyme

from the predator cells “drilled”

through the protein membrane of

their victims, obliterating them in

under an hour and sucking up DNA

in the process (Nature Chemistry, DOI: 10.1038/nchem.2617)

These protocells display habits,

such as moving and eating one

violence and crime by reducing

the amount of men in male-

dominated areas may backfire

(Human Nature, doi.org/brbb)

When women are in short supply, men perceive them as

being amore valuable resource,

says Schacht Consequently, men must be more dutiful to win and retain a female partner Inan

abundance of women, men are

spoilt for choice and adopt promiscuous behaviour that

from living, interacting beings But

because they aren't actually alive -

they can’t replicate on their own and

they don't evolve - their behaviour

highlights how easily we might

be deceived in our search for

extraterrestrial life, says Steven

Benner at the Foundation for Applied

Molecular Evolution in Alachua, Florida “If you were to see that ina

“If you were to see this type

of behaviour ina sample from Mars, people would

mistake it for a life form”

sample from Mars, people would be

writing PhD dissertations about this being a life form,” he says

Eventually, Mann’s team hopes to

build a community of even more types

More women, more fights

brings them into conflict

with other men, and makes

them more likely to commit sex-related offences

“Work in animals also shows quite similar findings to ours, that when females are abundant

and males rare, males are more

violently competitive, more promiscuous and less likely to invest in offspring,” says Schacht

“Schacht’s findings are in line

with ‘mating-market theory’,”

says David Buss of the University

of Texas at Austin The results

tally with his own work, which

shows that when women

outnumber men, there are more short-term relationships,

divorce rates increase and men

become more reluctant to

commit to one partner

The upshot, says Schacht, is that men alter their behaviour

to suit conditions of supply and demand “In some situations they

will be much better behaved, and

in others they will be much more

prone to nasty behaviour,” he says

The work also has implications

for crime prevention, he says:

“We are overly focused on male excess when we should reorient

to places with more women.”

Andy Coghlan @

of artificial cells, all interacting and

exchanging information This could

beused in medicine and materials

science, Mann says “Ultimately,

our vision is to think about protocell

ecosystems,” he says

Although the protocells aren'talive,

their predatory interactions suggest

that competition is possible between

non-living things, says Neal Devaraj at the University of California, San Diego

That brings the field one step closer

to perhaps someday demonstrating

protocell evolution and even artificial

life, he says

Inthe meantime, Devaraj says it

would be interesting to see if the

predator protocells could recognise

a biological signature Such killer protocells could then be used to battle

particular disease-causing bacteria

Emily Benson mi

WHERE THE

WILD THINGS ARE

Discover strange and stunning animals, epic landscapes,

extreme explorers alongside the best wildlife photography

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doesn't typically happen when breastfeeding ceases

Instead, it seems that epithelial cells eat their dead

when breastfeeding is over

WHEN a woman stops breastfeeding, her breasts go from

milk-producing factories to regular appendages Now a

switch has been found that controls this transformation,

and it could have implications for treating breast cancer

During pregnancy, epithelial cells in the breasts

proliferate and form structures that make milk Once

breastfeeding stops, these structures self-destruct But

how does the body remove all that debris? Usually,

immune cells would do that job, gobbling up the dead

cells Yet with that amount of material, you'd expect

neighbours Nasreen Akhtar at the University of Sheffield,

UK, wondered if a protein called Rac! is involved She

found that mice lacking the gene for Racl weren't able

‘to feed pups beyond their first litter Without Racl, dead

cells and milk flooded the breast when lactation had

finished, triggering inflammation and impairing tissue

regeneration (Developmental Cell, doi.org/bq8q)

Although prolonged breastfeeding reduces overall

cancer risk, women have an increased risk of developing

breast cancer for 5 to 10 years following pregnancy One

theory is that inflammation after breastfeeding may fuel

cancer growth Given Racl suppresses this inflammation, significant pain and inflammation - something that

Giant lurkers may explain lonely planets

LONELY planets can blame big

bullies Giant planets may evict

most of their smaller brethren

from orbits, partly explaining why

the Kepler space telescope saw so

many single-planet systems

Up to 80 per cent of the

planetary systems Kepler has

discovered appear as single

planets passing in front of their

stars The rest feature as many as

seven planets -—a distinction

14 | NewScientist | 8 October 2016

dubbed the Kepler dichotomy

What’s more, multi-planet

systems tend to have circular

orbits all in the same plane, and

singletons’ orbits tend to be elliptical and tilted

Now, a pair of computer simulations suggest that hidden giants may lurk in these single systems They show that

gravitational interactions

involving giants in outer orbits

it may be a new target for cancer therapies

can eject smaller planets from the system, nudge them into their

stars, or send them crashing into

each other The giants pull the few

remaining inner planets into more

elliptical and inclined orbits—the

same kind seenin many of the

single systems Kepler has spotted

else must be at work as well

Stars’ spin turns weather weird

LIKE a movie on fast-forward,

planets orbiting rapidly spinning

stars might whip through their seasons in double time

Earth’s tilt gives our planet its

seasons But hot, massive “early-

type” stars can spin almost 100 times faster than the sun, creating

amidriff bulge The gas around the star’s equator is then further

from its centre, so it cools more

than other parts of the star’s

surface, while the poles remain

hot and dense

John Ahlers at the University of

Idaho in Moscow wondered how

this might change the seasons on

an orbiting planet If its orbit is

angled, it would be directly over

the star’s chilled equator twice in

each orbit, and would have two

summers and two winters a year

Ahlers found that difference

could mean the planet’s surface would oscillate rapidly between a boiling hellscape anda frozen

tundra (arxiv.org/abs/1609.07106)

Bee fossil reveals

early human abode

AFOSSILISED bees’ nest might

tell us a lot about a key early

human The skull of an apelike

Australopithecus discovered in

South Africa in 1924-knownas

the Taung Child -overturned our view of human origins It suggested humans evolved in

Africa, not Eurasia

Now Philip Hopley at Birkbeck,

University of London and his colleagues are studying a bees’

nest found at the same site The

bees would have nested on open

ground, so the rocks around were

probably formed in an arid habitat full of flowering plants —

and aren't cave rocks as previously thought This means there may be

more fossils beyond the small site

previously believed to have been

a cave (PLoS One, doi.org/bq8))

For new stories every day, visit newscientist.com/news

3D-printed bone

offers flexible fix

ABOUNCY, bendy, 3D-printed bone

could revolutionise implants for

facial deformities and

reconstruction

Currentimplants are often brittle

and so break easily and can’t be

remodelled during surgery Now, an

ink has been developed that can be

used to 3D print bone implants in

any size, shape and form - from leg

bones to entire skulls And because

the implants are flexible, they can

be cut into the perfect shape in the

operating theatre

The ink is made from

hydroxyapatite, a mineral found

naturally in bone, and PLGA, a

polymer that binds the mineral

particles together and gives the

implants their elasticity

“We were very surprised to find

when we squeezed an implant, it

bounced back to its original shape,”

says Ramille Shah at Northwestern

University in Chicago

Once in place, the implants are

rapidly infiltrated by blood vessels

and gradually turn into natural bone

(Science Translational Medicine,

doi.org/bq8r) This offers a cheap

and versatile way to repair an injury

Shah’s team calls the implant

material “hyperelastic bone” and

says it could be used for many

treatments, from dealing with

fractures and spine repairs to

implants to rebuild faces after injury

Milky Way's baby brother copies its star-shredding habit

THE Milky Way's brightest

satellite galaxy stands accused of the same crime as itself: tearing

apart a celestial object that

wandered too close

The Large Magellanic Cloud

is the brightest of more than

50 galaxies that orbit our own

Big spiral galaxies like the Milky

Way are known to tear up and

devour their neighbours,

including some of the Large Magellanic Cloud’s brethren

But the satellite galaxies

themselves have never been

observed doing the same

Sound blasting to

scare off whales

WARNING signals to deter minke whales from wind farm

construction sites are being

tested in Iceland The deterrents involve a series of amplified

electronic pulses projected into the water, and were originally developed to stop seals from stealing farmed fish

A 40-day trial run by the Carbon,

Trust is looking at whether they

might also help ward off whales during noisy pile-driving activity

inthe North Sea The deterrent

pulses, while annoying to whales,

aren’t harmful

“Noise pollution threatens whales because it interrupts their normal behaviour and can drive them away from important

breeding and feeding areas,” says

Danny Groves from the charity Whale and Dolphin Conservation

“Excessive noise levels

underwater can also cause injury

and, in some cases, death.”

Minkes are thought to be abundant in many of the areas

earmarked for wind farm

development, which can be

noisy for days on end

The hope is that the pulses could make whales avoid the area during construction The results are expected early next year

Now Nicolas Martin of the University of Strasbourg in France and his colleagues have spotted

what looks like a globular cluster—

a tightly packed group of stars —

in distress The cluster is on the outskirts of the Large Magellanic

Cloud, about 42,000 light years from its centre

The team found the star cluster

in Marchas part ofa search called the Survey of the Magellanic

Stellar History (SMASH), so they named the cluster SMASH 1 And

it does indeed seem headed fora

smash-up It is elongated, and its

long axis points right at the

Large Magellanic Cloud, suggesting that the galaxy’s

gravity is yanking it apart

Still, if the star cluster has been

orbiting the galaxy fora long

time, it is strange that the destruction is occurring only now

The cluster may have originally

circled the nearby Small

Magellanic Cloud, whose weaker

gravity didn’t have the same

effect Only recently did the Large Magellanic Cloud snatch the

cluster and begin shredding it

(arxiv.org/abs/1609.05918)

Here's how budgies avoid collisions

HOW do birds avoid crashing into

each other when approaching

head-on? They have an inbuilt

preference for veering right

Mandyam Srinivasan atthe

University of Queensland, Australia,

and his colleagues uncovered the

simple trick when filming pairs of

budgerigars flying towards each

other in anarrow tunnel

During more than 100 tests, the

birds moved to each other's left side

in 84 per cent of cases, andnever

crashed They also tended to fly past

each other at different heights,

which prevented mid-air collisions on

the rare occasions that one swerved left (PLoS One, doi.org/bq8h)

Group hierarchy may dictate which bird opts to fly above the other

“It looks like the dominant birds

prefer to go lower,” Srinivasan says

“Maybe it’s more energy efficient and easier to go lower than higher,

so the non-dominant bird is forced

to gainaltitude.”

These crash-avoidance strategies

have evolved over 150 million years

in birds and may inspire anti-collision

systems in drones, “especially now

that drones are being built in large numbers”, says Srinivasan

8 October 2016 | NewScientist | 15

THE SECRET SCIENCE IN YOUR HOME

Fabric care: the

secret revolution

Fabric care used to be just about stain removal Now clever

chemistry can also keep clothes looking newer for longer

YOU'RE probably familiar with the life cycle of stains, lift them off fabric and lock them in the

a T-shirt At first, you wear it with pride, perhaps _ water ready to be rinsed away

washing it reluctantly to preserve its newness But other types of stains are more stubborn,

But as the luster fades, you demote ittohouse _ for example, some foods and body fluids

wear before eventually consigning its faded So this detergent also includes enzymes,

glory to the back of the wardrobe biomolecules that can attack the offending

Washing plays a key role in this life cycle grime They include proteases that break down

Improper washing may cause colors to fade, proteins, lipases that fragment fats and oils, as

fabrics to stretch and seams to break It'seasy _ well as amylases that carve up carbohydrates

to feel that your cherished outfits Water is crucial for hydration but it can also

deserve better Why does hinder the cleaning process Hard

The answer is that it detergents usually contain

needn't The technology to water softeners, known as

keep clothes looking new builders and chelating agents,

for longer is already in the ` which take metal ions out

detergents and fabric & of circulation Finally, special

conditioners developed by ~~ ™ polymers keep dirt suspended

scientists at P&G, one of the — during the wash cycle, helping to

companies of clothes this can cause

More than 800 scientists and engineers from

40 countries, based at three state-of-the-art Cool chemistry

innovation centers in Brussels, Newcastle and P&G's detergents also contain “optical

Cincinnati, are developing and testing a new enhancers” that are deposited on fabrics

generation of fabric care products that are making them look whiter and brighter

changing the way people think about their Dr Neil Lant, a research fellow at P&G’s

clothes and how they care for them Newcastle Innovation Centre in the UK and

At the heart of this is the smart chemistry his colleagues, are on a mission to challenge

in P&G's detergents, like that in Tide Pods® what's possible by designing detergents that

(above) These contain surfactants, long stringy deliver powerful stain removal and keep that molecules that bind to water at one end and T-shirt looking good too “Detergents need Lane ees # tot” 9741,

oily substances at the other Aided by agitation _ to clean and keep clothes looking newer for l4 x h

during a wash, these help to break up fatty longer,” he says The team search for ways

“Th ti to make key ingredients work better in colder

e new generation and quicker washes For example, they have

improving the world, company Novozymes to redesign an existing

one wash at a time” enzyme that preferred higher temperatures

Ẹ

FABRIC PROTECTION

The fabric conditioner Downy makes clothes softer and smell fresher But it

has another crucial role, says Dr Renae

Fossum, principal scientist at P&G’s

Cincinnati Fabric and Home Care

Innovation Center in Ohio It protects

garments against aging

Downy is relatively simple

chemically It has a water-loving

head atop a long, fatty tail When dispersed in water, these molecules

form spherical vesicles with the heads

on the outside and the fatty tails inside

“When the vesicles touch a fiber,

they break and spread out to form

a lubricating layer,” says Fossum

This has multiple benefits “It

reduces the friction between fibers

so they can return to their original

positions more easily,” says Fossum

This process helps garments

keep their shape It also stops fibers,

especially cottons, from splitting and

creating fuzz And it maintains the

color vibrancy That’s because much

of the color fade from washing isn’t

the result of dye loss but increased scattering of light reflected from

damaged and disordered fibers This

causes the fabric to look duller and

lose its sheen

Downy combats this by keeping fibers smoother and aligned, so that

light reflects uniformly from them This

keeps the colors bright and vivid and helps clothes look newer for longer

ADVERTISING FEATURE

The job of P&G’s researchers is complicated

by trends in the fashion industry to use more synthetic fabrics Since 1990, polyester has

been replacing cotton as the most common

clothing fiber because of its low cost and durability More recently, the trend for figure- hugging and sporty-looking casual clothes -

“athleisure” wear - has introduced more

elastane, or Lycra®, into clothing

“The big problem with these synthetics

is that they are magnets for grime and bad odors,” says Lant Anything oily sticks strongly

to synthetic fibers, including the 20 grams of

greasy sebum that an adult’s skin produces every day

Elastane fibers are also relatively sensitive and prone to damage, potentially leading to

loss of stretchiness Tide Pods® contain

chelants and crystal growth inhibitors to

help prevent this loss and avoid the sag

It's a wrap

All this smart chemistry has to be carefully packaged The latest of P&G's detergents is the

Tide Pods®, which deliver just 28 milliliters of

detergent per wash, half the standard dose

They took 8 years to create, yielded 50 patents and were tested on 8 tons of laundry

The Tide Pods® are made of polyvinyl!

alcohol film, which is soluble in water The film must be strong enough to survive shipping, stable enough to survive months in storage

and yet quick to dissolve in a washing machine

“That meant we needed a detergent with alow

water content,” says Annick Vandeputte, senior

scientist at P&G’s Brussels Innovation Center

“Less than 10 per cent of what's in there is water.” The Tide Pods® keep ingredients apart in three chambers until the moment they combine in the wash

They are a hit with consumers who want clothes to look newer for longer and are easier

for the less experienced, such as students, and

for seniors and the visually impaired who may

have trouble measuring powders and liquids

There are other advantages too An important goal for P&G is sustainability - super compact Tide Pods® use less detergent for

each wash and colder, quicker washes are

better for your clothes and use less energy too

For Lant, Vandeputte and their colleagues, that’s important: their new generation of

detergents is improving the world one

wash at a time And keeping your T-shirts

looking newer for longer

More at: www.us.pg.com

ANALYSIS NORTH KOREA

Ready for launch?

How much should we worry about Kim Jong-un’s nuclear plans

and what can we do to stop them, asks Debora MacKenzie

IT HAS been a record year for

North Korea’s nuclear ambitions

The secretive nation tested its

fifth nuclear device last month,

the second test this year and the

largest so far Remote monitoring

put the underground explosion at

10 to 15 kilotons, about the size of

the Hiroshima bomb Days later, it

conducted its biggest-ever test ofa

long-range rocket booster

“The threat has now reached

adimension altogether different

from what has transpired until

now,” Japanese prime minister

Shinzo Abe told the UN after the

nuclear test “We must thwart

North Korea’s plans.”

But how? The North has several

times agreed to limit its nuclear

plans in return for aid or security

guarantees, but these deals have

always fallen apart Now the fear is

it won't give up its nukes- unless

it collapses, which could be worse

Before Kim Jong-un became

leader in 2011, the nation’s nuclear

threat seemed constrained “It

had limited fissile materials and

nuclear tests,” says Siegfried

Hecker at Stanford University in

California, and no way to launch

Kim accelerated development

(see timeline, below) and the

country now claims it can fit

nuclear warheads on missiles

North Korea's nuclear path

“Tt is very likely that North

Korea has a nuclear weapon that

could hit South Korea or Japan,”

says Joe Cirincione of the

Ploughshares Foundation, a US

think tank It may soon even be able to hit the continental US,

making North Korea a top priority

for the incoming US president

How can we tell the North’s true capabilities, given its secrecy?

“Itis very likely that North Korea has a nuclear weapon that could hit

South Korea or Japan”

While seismographs record the explosive power of a bomb, there

is no way to confirm its physical

size, but we do have clues

First, we can look to history

The nation is at a significant point inits nuclear development, says Jeffrey Lewis at the Middlebury

Institute of International Studies

in Monterey, California The US,

UK, China, Russia and France had all shrunk their warheads by their fifth tests North Korea should have made similar progress

The nuclear material used

can also hint at its size Outside

observers think the last two tests

were fission bombs boosted by hydrogen isotopes These release

neutrons ina thermonuclear reaction that produces more explosive force per kilogram of

fissile material, usually enriched

uranium or plutonium Satellite

images confirm that a plant

visited in earlier inspections,

which could be used to make the

required isotopes, is now finished

The North’s early tests released radioisotopes that could be

detected remotely These showed

they were plutonium devices

Hecker, who has visited North

Korea’s main nuclear facility in Yongbyon, says it probably has enough plutonium for six to eight bombs and produces another

bomb’s worth per year

North Korea also has uranium

Based on satellite images anda

2010 visit to its enrichment plant,

Hecker calculates that it has

400 kilograms of highly enriched

uranium (HEU), 16 bombs’ worth,

and can add six bombs per year

Smaller warheads

The recent underground tests

vented no material, so we don’t

know what the devices were made

of But descriptions of a warhead released by the country in March suggest it is using nested shells of plutonium, HEU and hydrogen

The nation’s nuclear programme has developed over the past three decades, but has recently accelerated to make 2016 a record year

nuclear test,” he says

This design allows for smaller

warheads, and hence more of

them David Albright at the

Institute for Science and International Security in

Washington DC calculates that

Kim now has 12 to 20 nuclear

weapons at his disposal By 2020,

North Korea could have 50 to 100,

he says, and could field acrude

thermonuclear weapon witha

yield approaching 100 kilotons

Who could it target? This year saw tests of conventional missiles

launched from land and

submarine that reached Japanese

Nuclearfacility| Agreed Framework Leaves Nuclear UN Security Council imposes limited UN Security Council

built at Yongbyon signed with US| Non-Proliferation Treaty sanctions, Taks resumewith US and others, expands sanctions

© Known missile tests (incomplete)

@ Nuclear tests (kilotons)

© Satellite launch

18 | NewScientist | 8 October 2016

US relations break down Ejects|

inspectors and resumes plutonium production|

Talks cancelled when US president George W Bush callsit an outpost of tyranny Kim Jong-un takes over

s=—===——— ———=—— = -——-— — -— -—— —— —— -=—-——— -——

For daily news stories, visit newscientist.com/news

waters -—and could fly further

These short-range missiles could

carry warheads that weigh

between 700 kilograms anda ton

To hit the US, it needs a lighter

warhead, a way to slow it down

in flight and heat shields for re-

entry Photos released by North

Korea in March showed tests of a

heat shield and in April it showed

off a stationary test of the KN-08,

acopy of a Soviet intercontinental

ballistic missile (ICBM) This

could launch a 500 kg warhead

as far as Washington DC, says

John Schilling of Aerospace

Corporation in California Flight

tests might be only a year away

But North Korea is unlikely to

nuke the US, given the chances ofa

devastating response Lewis says it

only wants ICBMs to deter the US

from striking first, as the mobile

KN-08 would survive to retaliate

The North is more likely to aim shorter-range weapons at the

ports and airports needed to bring

in US troops to defend South

Korea, he says: “The goal for the

leadership is survival, and if

troops move in they have nothing

to lose.” South Korea has missile

defence, but it is only partial

Stop the bomb

How do we stop all this? “There

must be talks,” says Joel Wit at

Columbia University in New York

“They may not work, but what we

have now is guaranteed to fail.”

Talks almost worked before

“There have been several efforts

that have successfully delayed

North Korea’s nuclear progress,”

says Albright “But they

MISSILE TO THE MOON

North Korea's declaration in August

that it intends to putits flag on the

moon was greeted with derision

Experts say their rocket could get

there, buta lander is beyond their

current technology

Still, the nation looks determined,

attempting satellite launches despite

accusations that they are a front for

missile development

Are they? Every nation witha space programme once used

launchers that doubled as missiles,

and China still does, says John

Schilling of Aerospace Corporation

in California He thinks North Korea's

space programme taught it about the multi-stage rockets it needs for

long-range nuclear weapons

ultimately failed.”

In 1994, North Korea and the US

signed the Agreed Framework

The North pledged to give up its spent fuel, accept inspectors and

stop plutonium production in

return for nuclear power plants that make less plutonium The US promised no nuclear strikes and

to phase out sanctions

“It’s the best deal we could have

gotten, and we lost it,” says Lewis,

as George W Bush took a tougher

enforcement of sanctions is

crucial — and it is unlikely to hurt

North Korea enough to force concessions, for fear the regime might collapse

“Beijing doesn’t like a nuclear

North Korea on its border,” says

Lewis “But it certainly doesn’t

want a collapsed nuclear state.”

So what can be done? It might

help if Pyongyang felt less

threatened, an approach that

line Sanctions remained, thenew “There must be talks

power plants were delayed, and in

2002 the US accused North Korea

of secretly enriching uranium

The year after, North Korea left the agreement, and the Nuclear

Non-Proliferation Treaty

Since then talks have repeatedly restarted only to be scuppered by the North’s reactions to perceived aggression, including satellite launches condemned by the UN

as banned missile tests (see

“Missile to the moon’, below)

Now the US will talk only if North Korea agrees to freeze its programme The North refuses

That leaves just trade sanctions

to put pressure on the nation

Both Donald Trump and Hillary Clinton want to tighten these But nearly all North Korea’s foreign

business goes via China, whose

But now, he says, space and

missile development have parted

ways North Korea’s Unha-3 launcher

has upper stages with small engines

perfect for putting a satellite in orbit,

but too weak for an intercontinental

ballistic missile (ICBM)

COVERT OPS

Yet the North’s space ambitions can

also further its military ones To make

anuclear ICBM, the country needs a

heat shield to protect the warhead on

re-entry They could test one

covertly, suggests Schilling, by flying

itona “satellite” which falls to Earth

We could soon see North Korea

just tested a larger booster engine

that may launch later this year

They may not work, but what we have now

guaranteed to fail

helped South Africa give up its

nukes in 1989 Last month, North

Korea’s foreign minister Ri Yong

Ho said they had “no other choice

but to go nuclear”, given annual

US and South Korean military exercises “aimed at the

occupation of Pyongyang”

It’s not just paranoia South Korea uses a mock-up of Kim Jong- un’s palace for target practice,

and the US has flown a nuclear- capable bomber near its border Confronting North Korea in this way is more likely to make

aconflict go nuclear, says Van

Jackson at the Asia Pacific Centre

for Security Studies in Honolulu

Instead, the US and others should

de-emphasise nukes in their deterrence, giving North Korea’s leadership greater security

That will be impossible if South

Korea or Japan get their own

nuclear weapons Domestic pressure to do that is growing, and Trump backs a nuclear Japan Philip Jun of the Ploughshares Foundation fears that a military miscalculation—say a North Korean missile test wildly off course—could make the heavily

armed peninsula explode

Despite their spotted history,

talks seem the only option “No

country has ever been coerced

into giving up nuclear weapons,

but many have been convinced

to,” says Cirincione None of them,

however, were rogue states that already had nukes &

8 October 2016 | NewScientist | 19

COMMENT

Going out on a limb

When It comes to a Brexit deal, the science of strategic thinking

suggests delay Is the UK's strongest hand, says Petros Sekeris

PRIME Minister Theresa May has

said she will trigger Article 50 of

the European Constitution by

next April to begin the UK’s exit

from the European Union This

will set a two-year clock ticking

for talks to finalise withdrawal

Has she made the right

decision? While we can try to

answer that in many ways, game

theory is science’s best bet This

mathematical construction of

behaviour tries to predict how

opposing sides in strategic

settings will act to maximise the

chance of achieving their goals

It relies on three key inputs:

who's playing, their goals and

when decisions can be made

As far as the who goes, this is

not just about the UK interacting

with a single European block

Instead, politicians from all

28 EU nations are motivated by

domestic concerns UK elections

are due in May 2020 Across the

The UK has conflicting goals: restricting movement of people while keeping trade open The Brexit campaign’s immigration

focus means May’s mission is to

get a face-saving agreement on this while keeping trade tariff- free The votes of Bremainers may

be vital for her re-election hopes

in 2020, many working in sectors

at risk if trade barriers go up

For the EU, free trade without

freedom of movement has been a

red line, and it also wants to deter

more nations from quitting by

ensuring an economic cost to

Brexit Plug these factors into the equation and it looks like an insoluble stand-off

What about the when factor? Game theorists have long known delaying tactics can be potent in

Sting in the tail

If insects have feelings, do we need more

humane fly spray, wonders Peter Singer

YOU might want to think twice

next time you reach for the fly

spray A willingness to draw

parallels between mammals

and insects is raising significant

ethical questions about how we

ought totreat them

In May, researchers in Sydney,

Australia, suggested that the main

part of the insect nervous system

20 | NewScientist | 8 October 2016

works ina similar way toa mammal’s midbrain, and might provide the capacity for the most

basic form of consciousness,

subjective experience

Now a group in London says

that bumblebees appear to show

“positive emotion-like states”

(see page 9) Their study cites other papers from the past five

years that indicate a growing acceptance that invertebrates may show basic forms of emotion

This is not so surprising, given evidence of intelligence in

cephalopods such as the octopus

But to grant insects emotions

opens a whole new can of worms

The authors say that emotional states in bees are not necessarily

conscious, but could be In ethical terms, consciousness —and hence

the capacity to suffer—is crucial

Rules to protect lab animals are

“If insects share the

capacity for suffering, they

too should be covered by lab animal regulations”

typically limited to vertebrates because there is little doubt that they can suffer In the UK, the

common octopus won protection

in 1993, and later the EU included

all cephalopods If insects, or at

least some, share a capacity for suffering, that would mean they

too should be covered

This would raise questions about the ethics of bee research In one experiment, “aversive stimuli”

were used: bees were temporarily

trapped in a device to mimic

being caught by a spider If bees

are capable of feeling fear, then presumably this was distressing —

in which case, was the finding

important enough to justify that?

For more opinion ai

the right circumstances, and

everything suggests that this is

the right approach here Invoking

Article 50 immediately would

have put the UK ina weak

position, because Europe needs to

be tough in the face of the threat

of rising right-wing extremism

So whenis the optimum date

to trigger Article 50? In mid-2019,

EU parliamentary elections will

take place and EU budgets will

be decided by the Commission

While in the EU, the UK has a veto

over the budget, and 10 per cent of

the European Parliament’s MEPs

Still being “in” Europe then would

win the UK added leverage

There is also the chance that

positions in France and Germany

will soften after elections —in

spring and early autumn 2017 —

as the need to impress voters who

want to see Brexit punished fades

Invoking Article 50 should

ideally be done no earlier than

May 2017 to retain influence in EU

elections and budget-setting and

to be close enough to German and

French elections to minimise

their influence

Will declaring Article 50 sooner,

as Theresa May pledged, hit hopes

of an optimal UK deal? All will be

Petros Sekeris is a game theorist at

Montpellier Business School, France

But if bees do have this type of

consciousness, that might not

mean that all insects do We may

hope that mosquitoes, flies and

ants don’t, so we can get rid of

them without worrying about

inflicting pain

And being capable of suffering

would not grant insects a right to

life What it would mean is that we

should reconsider how we stop

them biting us or contaminating

food, so we minimise any pain we

may cause Bi

Peter Singer is professor of bioethics at

Princeton University Ethics in the Real

World, a selection of his essays, is out

now (Princeton University Press)

.com/opinion

SpaceX Mars plan is

clever but unconvincing

Lisa Grossman

ELON MUSK has unveiled a spectacular

plan to send humans to Mars, but! am

not convinced he can really pull it off

Last week at the International

Astronautical Congress in Guadalajara,

Mexico, the SpaceX founder laid out

his vision for building the largest

rocket ever, to launch a100-person, spaceship on an 80-day trip to Mars

Once at the Red Planet, the

spaceship will land on its feet using

retro-rockets, and the astronauts will

emerge on to a cold, dusty world

Meanwhile, the spaceship will make its own methane fuel for a return

journey to pick up more settlers Musk

also plans to send supplies to Mars

every two years, starting in 2018

Much of this strikes me as clever

and innovative, but it may not be

enough Musk wants to send the first humans in roughly 2024, although he

was “intentionally a bit fuzzy about

this timeline” That only gives Spacex three chances to launch enough kit

This is where the plan breaks down, Musk seems to think his job stops once people reach Mars, and that keeping

them alive is someone else's problem

His only mention of growing food

on Mars assumed that we had already terraformed the planet He was vague

on how the settlers would generate energy He said nothing about Martian dust, which covers solar panels and

could harm astronauts

When asked about health risks in

transit, Musk suggested they would be

minor That runs counter to data from

the Curiosity rover, which found that

around trip to Mars would expose

astronauts to seven times the

radiation dose they would get during

six months on the International Space

Station - well over NASA's safety limits

“Spend your life savings on

a one-way cruise, followed

by a lifetime of physical labour? Sign me up”

It may be that none of these issues are showstoppers for SpaceX But equally they seem not to be the first problems on Musk’s list And that's odd,

considering his Mars colony is meant

to be humanity's back-up plan

"The thing that Mars really

represents is life insurance, ensuring

that the light of consciousness is not

extinguished, backing up the biosphere," he said, “It’s not about everybody moving to Mars, it’s about becoming multiplanetary.”

Sowho will found this brave new world? The rich Musk hopes to get the cost of a ticket to Mars down to around

$200,000 and described the trip as a

luxury cruise, with restaurants, movies and zero-G games

But life on the Red Planet will be

much less cushy: “Mars will have a

labour shortage for along time so jobs will not be in short supply,” he said

So, you spend your life savings on a one-way Musk cruise, followed by a

lifetime of physical labour ona cold,

airless desert? Sign me up

That's not Musk's vision, of course SpaceX's video of the plan ends with

Mars quickly growing more blue and

lush, as if by magic But if we are going

to assume future magical terraforming

powers, | would rather we apply them

to the one planet we can already live

on, and keep Earth habitable,

And who will pay for all of this?

Musk said the initial mission will cost around $10 billion, and wants backers

fora public-private partnership

Still, even talking about sending

humans to Mars in a semi-realistic way

is thrilling Musk is highly driven and

while vague, his plan is not impossible

I doubt he will keep to that

2024 timeline, though Musk himself admits that staying on schedule is

not his forte Even his talk started half

an hour late

8 October 2016 | NewScientist | 21

TECHNOLOGY

[t's just Common sense

To build a truly adaptable artificial intelligence, we first need to let it

know how our world works, says Sally Adee

PONG isa gloriously simple video

game: youcontrol one paddle,

aiming to bounce the ball past

your opponent’s paddle Artificial

intelligence has learned to play

it so well that it can easily beat

human players But try to get the

same AI to play Breakout, a very

similar paddle-based game, and it

is utterly stumped It can’t reuse

what it has learned about paddles

and balls from Pong, and has to

learn to play from scratch

This problem dogs modern

artificial intelligence Computers

can learn without our guidance,

but the knowledge they acquire is

“A computer is like a child

who learns to drink froma

bottle but cannot imagine

how to drink froma cup”

meaningless beyond the problem

they are set They are like a child

who, having learned to drink from

a bottle, cannot even begin to

imagine how to drink froma cup

At Imperial College London,

Murray Shanahan and colleagues

are working on a way around

this problem using an old,

unfashionable technique called

symbolic Al “Basically this meant

an engineer labelled everything

for the AI,” says Shanahan His

idea is to combine this with

modern machine learning

Symbolic Al never took off,

because manually describing

everything quickly proved

overwhelming Modern AT has

overcome that problem by using

neural networks, which learn their

own representations of the world

around them “They decide what

is salient,” says Marta Garnelo,

also at Imperial College

Neural networks have delivered

22 | NewScientist | 8 October 2016

the big Al advances of recent

times, but the representations they use are incomprehensible to

humans and can’t be transferred

to other neural nets So for each

fresh task, neural networks must

build new ones They learn slowly,

relying on big data to chew on and plenty of processing power

Shanahan’s work aims to tie

symbolic AI to the autonomous

learning of neural networks,

allowing some knowledge to

transfer between tasks The prize is learning that is quick and requires less data about the world

As Andrej Karpathy, a machine learning researcher with the firm Open Al, put it ina recent blog

post: “I don’t have to actually

experience crashing my car into

awalla few hundred times before Islowly start avoiding to do so.”

Symbolic Alalso helps us understand how machines make

decisions, something we often

can’t do “Neural networks don’t

convert the reality around them

into the kinds of symbols that we use,” says Joanna Bryson, an Al researcher at the University of

CONVERSATIONAL SKILLS

You'd be forgiven for thinking

computers have language all figured

out Google can translate between

tens of tongues, and natural language

processing lets us speak to software

agents like Siriand Amazon's Alexa

Butas Siri’s many noted missteps

attest, a computer really has no idea

what you're talking about It breaks

your speech down, gloms on to

keywords and makes a good guess

at what you're asking

For a machine to carry on a real conversation, it must understand

Bath, UK By “symbols”, Bryson

and other AI researchers mean

any kind of reusable concepts or

labels, such as words or phrases

Shanahan and Garnelo’s hybrid architecture retains neural

networks’ ability to interpret the world independently However,

the researchers combine that

with some basic assumptions that reflect the way we understand the

world: things don’t usually wink

out of existence for no reason;

objects tend to have certain

attributes like colour and shape

This allows the hybrid to build rudimentary common sense “Our little system very quickly learns a

set of rules,” says Shanahan These

let it handle unseen situations that are beyond a purely neural- network-based system

The team tested the hybrid’s

abilities ona simple board game

Amix between tic-tac-toe and

Pacman, it features a cursor

moving around a board littered with noughts and crosses Hitting aOorx scores or loses a point

respectively Crucially, the distribution of the symbols is

what you're telling it That's amuch

higher-order problem, says Joanna

Bryson at the University of Bath, UK,

requiring an ability to understand

symbols and meanings

The power to fluidly describe,

understand and interact with the

world would bring us close to

artificial general intelligence,

something broadly acknowledged

tobe a distant prospect Hybrid

systems like the one being developed

at Imperial College London may point

toa way forward (see main story)

đifferent every time, and the

hybrid AI had to work out what

actions were associated with

reward “IfI go get that o, that’s

good If! go get that x, it’s bad,”

says Shanahan

When pitted against “Deep Q-Network” (DQN), an algorithm, created by Google's subsidiary DeepMind, the AI did extremely well, beating its score on randomly generated boards that neither

architecture had seen before

(arxiv.org/abs/1609.05518)

Crucially, the hybrid was able

to transfer what it had learned

across games After 1000 training

sessions, DQN managed a positive score on half of its games But it took the hybrid only 200 sessions

to arrive at a strategy that earned a positive score on 70 per cent of its games Shanahan puts it down to

it being able to port a rudimentary

strategy across different games

“J don’t want to hype this up

For more technology stories, visit newscientist.com/technology

Mobile 3D printer lets you make on the go

too much,” says Shanahan “It is

just a prototype The game is

simple, and the hybrid beat an

old version of DON.”

Still, the implications of

transferable learning are fairly

significant “Being able to pick up

regularities at different levels isan

important component of human-

like intelligence,” says Bryson

This kind of hybrid learning is important for robotics Powerful

learning that involves many layers

of neural networks is hard to apply

there because of the volume of

data needed, says Coline Devin,

acomputer scientist at the

University of California, Berkeley

Devin sees hybrid architectures

as having a particular advantage

for driverless cars “They could use

deep learning to process camera

images,” she says, while accessing

a library of preset rules—like

stopping at red lights and carrying

on when they are green - which

PSs FH FS 00)

%2” 1/8 2%

It's good to learn on the job

wouldn’t need to be learned

In driverless cars, the symbol- based transparency of sucha hybrid is also crucial “Symbols area really important aspect of how we explain ourselves and

communicate with other people,”

says Bryson Coming legislation in Germany will require algorithms

to explain decisions they take in driverless cars By 2018, European Union citizens may have the right

to ask any automated system to

account for its decisions

However, the most startling

consequence of a workable hybrid

architecture, Bryson points out, is

that it could enable machines to convert their representations into reusable symbols — analogous

to language or words (see

“Conversational skills”, opposite)

“This experiment barely scratches the surface of what

we believe is possible with this

architecture,” Shanahan says & CHRISTOPHER

YOU know the feeling: you look

around and the one thing you urgently

need seems to have vanished Maybe

it’s akey, or an earring back, ora

specific spanner

Whatever itis, a new project aims

to help With a mobile app anda

pocket-sized 3D printer, this personal

fabrication kit lets you quickly print

what you need on the go

For several years, 3D printing has

been heralded as the next big thing

in manufacturing But Thijs Roumen,

a graduate student at the Hasso

Plattner Institute in Potsdam,

Germany, wondered why it has

yet to catch on for individuals

He likens his vision for 3D printing

‘to the rise of personal computing,

where computers evolved from

enormous machines into easy-to-use

handheld devices

“We were curious why 3D printing

never really made that transition,”

he says “What would the real world

rather than in a controlled office environment?”

First, Roumen and his colleagues

crowdsourced alist of objects people

wanted to be able to make when they were out and about, such as

akarabiner to fix a broken strap or

earplugs if someone were snoring

beside them on the bus Then the

team built prototype mobile printers

that could make these objects

The most successful was a

modified extruder pen, a kind of

handheld printer that spits outa

stream of plastic An app lets you look

up the object you want to make, then

shows the pattern you need to trace

on top of your phone screen to create

it In tests, the team printed a button fora shirt as well as a hex key to fit a

loose bolt ona bike accessory

The project will be presented at

the User Interface Software and

“This approach, where the

human and the machine

both do some stuff,

can get a better result”

Technology Symposium this month

in Tokyo, Japan

“I like this idea of moving entirely

from the mechanised and automatic

3D printer to using a pen,” says Daniel

Ashbrook at Rochester Institute of

Technology in New York The machine

can balance human imprecision, while

our motor skills offset the machine's

slow speed, he says

“This kind of hybrid approach,

where the human is doing some stuff

and the machine is doing some stuff,

can get a better result - especially

when you're not trying to be perfect,

you're just trying to get something

done.” Aviva Rutkin mi

8 October 2016 | NewScientist | 23

TECHNOLOGY

Plastic flower blossoms

Material morphs to its own beat, finds Sandrine Ceurstemont

IT’S blooming marvellous An

artificial flower can blossom when

you want, thanks to petals made

out ofa material that contains its

own version of a biological clock

“Nobody has ever done this

before,” says Sergei Sheiko at the

University of North Carolina at

Chapel Hill

Morphing materials are

interesting because they allow

objects to change shape, and

thus function They have been

mooted as a way to create medical

implants that are folded up for

insertion into the body then

change shape once inside But

they typically need a trigger to

start the process, like a change in

light levels, temperature or pH

“In certain situations, like

inside your body or in space,

external triggers are not

permissible or are ineffective,”

says Sheiko “You simply want

an object to change shape at a

“Morphing materials could

be used to create medical implants that change

shape inside the body”

programmed petals to

demonstrate the concept,

alongside a box that opened on

one side at a scheduled time

“Tt has great potential fora range of applications, especially

in biomedical engineering,” says Michael Kessler at Washington

Let's do the time warpagain

State University in Pullman,

who also develops transformable materials

To create the material, Sheiko’s

team tweaked the molecular

structure of a conventional soft

polymer A small proportion of

links between molecules ina polymer are permanent, allowing

the material to act like a spring,

snapping back to its original form

when stretched and released,

like a piece of rubber

But most of the bonds are shape-shifting, breaking and rearranging themselves over

time It’s these that the team

targeted: modifying the rate of shape-shifting let them control how the material changes over the

course of several hours (Nature

Communications, doi.org/bq8k)

“Most bonds snap ina split

second, so our goal was to extend their lifetime,” says Sheiko

Although the material can morph without an external trigger, the team found that tweaking pH and temperature gave them additional control

to speed up or slow down the transformation

Designing complex shapes proved difficult, so the team broke intricate designs into

building blocks that could each

be programmed to change at different times

Programming the material

to change at a constant rate was

easy But the team struggled to introduce a dormant period orto accelerate change at certain times

Their best solution was to give

an object an extra water-soluble

“skin” By tweaking its thickness

based on the desired time delay,

an additional clock could be

added to the system when it

was dropped into water

“We plan to explore this

further,” says Sheiko &

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26 | NewScientist |8 October 2016

Beautiful sludge

SINUOUSred streams of aluminium-processing

'waste and bright green vegetation light up this

aerialview ofanindustrial reservoir onthe lower

Mississippi river,about50 kilometres south of

Baton Rouge Atfirst glance, the vivid colours suggest beauty, butthe image is meantto cause

alarm, says photographerJ Henry Fair

Producing aluminiumfrom bauxite ore generates a toxic sludge called “red mud” thatis visible around the edges of the football-field- Sized area pictured here Whenasimilar reservoir containing the substance burstin Hungaryin 2010,four people were killed and there was catastrophic ecological damage

Fair wantsto getusto thinkaboutwhatwe

chooseto buy and throw away, as wellasthe environmental impact of something as simple as ailing to recycle an aluminium can

MU 1U (CO TC (0.220

things to people in a way that makes them

question, and hopefully think about, the impact,”

ee The photograph below is another birds-eye

view, this time of afield in Germany The shadowsr cast by surrounding trees have stopped some of 'the rapeseed plantsfrom flowering

'Both images are part of a series taken over 15

yearsfroma small plane and collected in the book

Industrial Scars, published by Papadakis this

Pree sues

Photographer

J.Henry Fair jhenryfaircom/aerial

80ctober 2016 | NewScientist |27

ˆCOVERSTORY

Going clean

Crack a simple chemical reaction and we don't

have to kick our addiction to fossil fuels,

seabirds writhing in liquorice gloop:

there’s no denying fossil fuels have an

image problem That’s before we even start

to factor in the grave risk continuing to burn

them poses to Earth’s climate But what’s the

alternative? Nuclear is expensive, renewables

are unreliable, and we are along way from

making batteries that could power our fuel-

hungry lifestyles Realistically, we are going

to be reliant on fossil fuels for a while yet

What we need is a way to exploit them without emitting any planet-warming carbon

dioxide Alberto Abanades thinks he has the

answer He isn’t a PR man for the fossil fuel

industry, and nor does he have anything to

do with various schemes to capture and bury

carbon emissions after the event He and his

research team think they have cracked the

problem using chemistry alone By simply

changing the way we liberate the energy

trapped inside natural gas molecules, we can

have all the benefits of fossil fuels— and none

of the guilt Too good to be true?

It’s easy to see why we love fossil fuels

Fora start, they are cheap and abundant

Discoveries of new resources and extraction

techniques such as fracking mean reports of

“peak oil” always seem exaggerated They are reliable, too— you can shovel coal or pipe gas

into a power station when the sky is cloudy

or the wind’s not blowing And they can be

: portable ~ simply fill a car tank with petrol

= and you are good to go

S CARRED landscapes, billowing smoke,

28 | NewScientist | 8 October 2016

says Jon Cartwright

We have tried to kick our fossil addiction

before During the oil crisis of the 1970s, all

the talk was of hydrogen The gas ticks a lot of

boxes as a fuel: it is non-toxic and the most

abundant element in the universe It is clean,

burning in air to create water vapour that

falls harmlessly back to Earth as rain It is

energy-dense—you could drive the 600-odd

kilometres from London to Edinburgh, or

San Francisco to Los Angeles ona single tank

And it can be burned in power plants, even competing cost-wise with fossil fuels once

carbon taxes are taken into account

“It’s easy to see why we love fossil fuels - they’re cheap, abundant and reliable”

In practice, things aren’t so simple Being light and tiny, hydrogen has an annoying

ability to wiggle through any material

designed to contain it Like petrol, it is

flammable, yet burns witha near-invisible flame Above all, it isn’t abundant where and

how we want it

On Earth, hydrogen isn’t a free agent It is only found bound up in compounds such as water Pure hydrogen can be generated by

splitting water molecules using electrolysis,

but that takes a lot of energy Or youcan extract hydrogen from coal or natural gas by

heating them with steam, but that generates

copious amounts of carbon dioxide

So it came as little surprise when, in 2009,

then US energy secretary Steven Chu, a Nobel prizewinning physicist, ditched funding for research into hydrogen-powered vehicles

Last year, Elon Musk, CEO of electric-vehicle manufacturer Tesla, summed up many

sceptical opinions when he labelled hydrogen

an “incredibly dumb” alternative fuel

Perhaps, though, we haven't been thinking

about it in the right way Natural gas is

essentially methane, a molecule of one carbon atom and four hydrogen atoms Rather than reacting natural gas with steam to liberate the hydrogen, Abanades, who is now at the

Technical University of Madrid, and his

team developed a deceptively simple plan

You “crack” the methane into its constituent

atoms — pure, clean hydrogen, plus inert

atomic carbon, or soot

If it were that simple, it would already have been done Breaking carbon-hydrogen bonds takes a lot of energy They only start to crack spontaneously at temperatures above 550°C

orso; normally, temperatures over 800°C are

needed But there is a bigger problem: the soot This scuppered an early attempt to make methane cracking industrially viable:

it coated the nickel-iron-cobalt catalyst used by chemists at the petroleum company Universal

Oil Products to improve the reaction rate at

lower temperatures Their solution was to burn off the carbon- making carbon dioxide

It’s been the same lament with methane

cracking ever since Soot clogs things up and »